I had to look up the walkthrough myself because it has been a while.
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Once you have paid the full guild debt (“pay guild” button in Lower Hallway), a raven will
appear the next morning
• You will be instructed regarding arrival of your assistant Nyx through the portal
• Using Code SuExSu (green/purple/green) with the already activated portal at 18:00 will
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That seems very basic. What does the portal do when you insert the three gems?
If I remember correctly once you select the right action in the UI, some interface opens and you have three empty slots to put the gems into.